FIG. 1 is a fragmentary perspective view of the rear end of a utility vehicle 10 having a liftgate 12 to which a factory-installed rear spoiler 14 is attached. A window panel 16 is fitted to and thereby forms an upper portion of liftgate 12. An exterior lighting unit in the form of a two-housing light bar 18 is installed underneath rear spoiler 14 and positioned adjacent an outer surface 20 of window panel 16. Light bar 18 includes a passenger side light housing 18p and a driver side light housing 18d. Three light heads 22 are attached to each of light housings 18p and 18d. The positioning of light bar 18 underneath rear spoiler 14 provides the vehicle driver maximum rear window visibility and eliminates a possibility of vehicle interior backflash.
U.S. Pat. No. 8,899,805 of Helterbrand et al. describes a conventional technique for mounting a light bar assembly, such as light bar 18, to a liftgate of a utility vehicle. Helterbrand et al. describes a light bar support formed with openings corresponding to locations of preexisting openings in the vehicle and mounting fasteners that can be used to attach the light bar support to the vehicle so that no other openings or alterations are required.
Helterbrand et al. states that the light bar support allows the light bar assembly to be readily mounted on the vehicle without modifications to the vehicle or the light bar assembly. The Helterbrand et al. method of mounting the light bar assembly to the liftgate on the vehicle entails removing the rear spoiler from the liftgate to set the light bar support in place between the rear spoiler and the liftgate, and thereafter passing the mounting fasteners, such as mount bolts, for the spoiler through the preexisting openings in the liftgate to secure the rear spoiler and light bar assembly to the liftgate.
FIG. 2A is an exploded view of rear spoiler 14 detached from a top side margin 24 of liftgate 12. FIGS. 2B, 2C, and 2D are pictorial views of the interior of rear spoiler 14, showing the locations of sealing gaskets 30, plastic spoiler retention clips 32, and point nuts 34 used to effect secure mating of rear spoiler 14 to liftgate 12. The light bar assembly mounting technique of Helterbrand et al. requires removal of rear spoiler 14 from the top of liftgate 12 and later reinstallation of rear spoiler 14 onto the top of liftgate 12. The rear spoiler removal and reinstallation process creates a potential for breakage of plastic spoiler retention clips 32, dislodgement of or damage to sealing gaskets 30, or loss of point nuts 34 or their associated mounting bolts. An upfitter installing the light bar assembly and faced with broken or loss of some of the mounting components may choose to reinstall rear spoiler 14 to liftgate 12 with fewer than the original number of or damaged mounting components used by factory installers. One or both of use of fewer than the factory-specified number of mounting components and use of damaged sealing gaskets would result in improper rear spoiler reinstallation and adverse consequences stemming from it.
What is needed is a system for and a method of installing an exterior-mounted light bar underneath a factory-installed rear spoiler on a vehicle liftgate that necessitates no disassembly, and thereby leaves intact the original mounting components, of the rear spoiler and the factory-installed liftgate spoiler sealing system.